Yuri Seijin Naoko-san

• Name — Yuri Seijin Naoko-san • Ja Kanji — 百合星人ナオコサン • Genre — Surreal comedy, yuri

• Type — manga • Author — Kashmir • Publisher — ASCII Media Works • Magazine — Dengeki Daioh • First — May 2005 • Last — April 2014 • Volumes — 5

• Type — ova • Director — Tetsuya Takeuchi • Writer — Tetsuya Takeuchi • Studio — Ufotable • Released — December 10, 2010 • Runtime — 6 minutes

• Type — ova • Director — Tetsuya Takeuchi • Writer — Tetsuya Takeuchi • Studio — Ufotable • Released — February 15, 2012 • Runtime — 30 minutes lit. Lesbian Alien Naoko-san is a Japanese manga series written and illustrated by Kashmir. The manga began serialization in the May 2005 issue of ASCII Media Works' monthly shōnen manga magazine Dengeki Daioh. A six-minute OVA adaptation by ufotable was released in December 2010, followed by a thirty-minute OVA released in February 2012.

A girl named Misuzu rushes home in order to see her elder sister, Naoko. When she arrives there, however, she finds her sister has been replaced by a self-proclaimed yurian named Naoko-san who seeks to conquer the world by 'yurifying' it.

• Naoko-san • Satomi Arai • An alien who comes from the Planet Yuri and takes the place of Misuzu's sister. She appears to have an attraction to young girls. She also loves to read Yuri books and anything that has to do with eroticsm. • Misuzu • Akari Harashima • A shy human girl whom Naoko-san comes into contact with. She misses her older sister and tends to have flashbacks of her. • Ryōta • Yukari Kokubun • Misuzu's androgynous little brother, who is often commanded to do weird things by Naoko-san. • Hii-chan • Ai Nonaka • Misuzu's best friend, who wears glasses. She appears to have a deranged crush on Misuzu and is also entranced with anything 'outer-space' related. • Okā-san • Kumi Tanaka • Misuzu and Ryota's mother. Like Naoko-san, she also seems to take an interest in erotic books involving young girls. • Dark Naoko-san • A robotic version of Naoko-san that lives on the roof of Misuzu and Ryota's home. Her personality resembles Misuzu's older sister. • Aya-chan • A pink-haired girl that attends the same school with Ryota and appears to be quite fond of him. • Ayako-san • Another female alien who is obsessed with yaoi. • Jashin-san • Another female alien with cyan hair who loves manga. She also has a crush on Naoko-san. • Naoko • Satomi Moriya • Misuzu's older sister who is strangely absent due to ambiguous reasons. • Chikan Seijin • Manabu Sakamaki • An alien that appears in the first OVA who comes from the Planet Molestrian (according to Naoko-san).

The original manga by Kashmir began serialisation in ASCII Media Works' Dengeki Daioh magazine from May 2005. The first tankōbon volume of the manga was released on December 9, 2006, and five volumes have been released as of April 26, 2014.

Two original video animation adaptations of the manga have been produced by Ufotable. The first one was six-minutes in length and was released on December 10, 2010. A second thirty-minute OVA was released on February 15, 2012, as part of an Anime Bunko lineup alongside adaptations of Gyo and Minori Scramble!. The opening theme is "Yuri Seijin Naoko-san" by MOSAIC.WAV, whilst the ending theme is "Photon Belt Tourist Hotel" by MOSAIC.WAV.